The present invention relates to a wheel bearing/constant velocity joint unit with a double row bearing which has been provided with at least one inner bearing ring which is separate from the wheel hub and which is axially held or tensioned by a formed collar provided at the wheel hub. The collar may be provided directly or indirectly via an intermediate part for holding the inner bearing ring. As a forming process, cold forming is particularly suitable.
Bearings of the above-mentioned type are known in the case of which the double row bearing comprises a separate inner bearing ring, which means that the bearing may be filled with a larger number of balls and that a radially compact design can be achieved (DE 34 18 440 A 1). Without having to carry out considerable modifications it would also be possible to use two separate inner bearing rings, thereby offering the same advantages in respect of the load bearing capacity of the bearing. The transmission of torque from the wheel hub to the adjoining joint is effected through longitudinal teeth inside the hub into which an attached shaft journal of the joint outer part may be introduced. Due to production-related tolerance fluctuations and wear in the longitudinal teeth, a clearance-free transmission of the driving torque cannot always and continuously be ensured, thereby causing noise and an increasing amount of wear in the joined areas. Because the collar engages the inner end groove of the outer bearing ring for tensioning purposes, it is not possible to introduce suitable solutions for the transmission of torque.
There are further prior art wheel bearing/joint connections in the case of which the transmission of torque between the wheel hub and the joint is achieved in an essentially clearance-free way by spur teeth or helical teeth on both parts (DE 32 19 747 A 1). However, this solution definitely requires bearings of the so-called third generation in the case of which the inner bearing rings are integral with the wheel hub. There is no other way of achieving an undivided end face of the wheel hub, the disadvantage of this design being that only a bearing type with a small number of balls can be used. The radial assembly space required for the bearing is correspondingly larger, and at the same time weight disadvantages have to be accepted. Even in this case, the outer diameter of the teeth is limited by the end-face outer diameter of the inner bearing ring, i.e. of the wheel hub in this case, which, for assembly reasons, cannot be increased by just any amount.